1. The video card needs to be low profile, if you were to keep the case.http://www.newegg.com/Product/Product.aspx?Item=N82E16814150657
2. You already have 3 GB installed, probably 1 + 2gb sticks. Just buy 1 2gb stick to match the one you have for a total of 4.
3. That processor will not work due to being FM2, your MB is AM3.
Lastly if you really want to improve the build you'll need a new/larger power supply, your 220w doesn't leave much room for improvement. Furthermore you'd likely be better served just starting from scratch because not much in that PC would make it into a new build. Although you do have a capable computer for everyday stuff so starting a new foundation entirely would be my suggestion.